1. Field of the invention
The present invention relates to a pen with adjustable holding structure, and in particular, to a pen which is convenient to write by leaning the specified finger to “lean” against the most comfortable place for writing. The pen is particularly suitable for writing for a long time, or for a person who has handicapped fingers necessary for avoiding fatigue or injury to the hand.
2. Description of the Prior Art
Well-known pens like fountain pen, ball pen, pencil (hard type), and brush (soft type for both writing and painting), are all used for a common purpose to make record by holding the pen in different ways.
FIG. 1 is a perspective view showing a posture of holding a pen. The most common cylindrical penholder “a” which fails to provide a place on its surface for exerting the force of a finger “g” causing the user to almost “grasp” the cylindrical penholder “a” so as to surely hold the penholder when writing such that the finger “g” is unable to be liberated from an intensive applying force during writing. The finger “g”, which being constantly exerting with force, is apt to suffer from blisters or dull aching in “N”, and possibly extending farther to the whole palm “h” as shown area “M” of FIG. 6. Especially to a child whose palm “h” is not yet grown, the finger “g” will usually slip down to the position of pen nib “b” as being unable to reliably hold the cylindrical penholder (see FIG. 2). As a result, the action of writing which is supposed to be smooth becomes so stiff like carving an object. And to the worst, the head of the child will incline closer to the desk as the sight is shaded by its own hand thereby gradually affecting the eyesight or even the normal growth of backbone.
Meanwhile, as shown in FIG. 3, other than the cylindrical pen, there is another one in a triangular prismatic shape “C” on the market that can quickly help the user to set the finger “g” at a proper location, but is still unable to solve the problems of “grasping penholder” or others as described above. The triangular penholder “c” is integrated into one piece and enclosed with a section of rubber sleeve “d” over the penholder “e” so as to provide an extra friction for enhancing the holding force thereby avoiding the slipping of the finger “g” during writing. However, as shown in FIG. 4, notwithstanding the thicker rubber sleeve “d” provides a comfortable feeling at the beginning of writing by grasping the penholder, the applied force “F” by the finger “g” will be gradually transmitted to the hard penholder “e” overlaid by the rubber sleeved so as to oppress the finger “g”. Besides, as shown in FIG. 5, in some cases, the lower fringe “f” of the rubber sleeved is formed into a flange to restrain slipping down of the finger “g”. Afterall, there is still no contribution to cure the writer's dull aching or blisters after grasping the penholder a while.
Base on these noticeable defects of the conventional pen structures, an improvement is seriously required.